Colorado Public Radio reported Tuesday that National Transportation Safety Board investigators said local authorities approved neighborhood construction on land adjacent to or once part of energy production.
An NTSB report said approval lacked documentation of line locations related to the well in Firestone in Weld County.
It found that three lines near the home weren’t properly abandoned by former owner Patina Oil and Gas Corp.
The blast killed two people and injured a third. The state began requiring inspections of underground flowlines near occupied buildings.
Occidental Petroleum has since taken over Anadarko.